Sometimes you want to install some app from the internet, and your Mac gives you an error that says something like "can't be opened because it's from an unidentified developer" or "...is damaged and can't be opened. You should move it to the Trash."
Well if you trust the app, and want to install it anyways. Just disable macOS Gatekeeper.
Re-enable gatekeeper with: sudo spctl --master-enable
We're some guys and gals in San Francisco who fix macs. We can remote in and help you with stuff. It's like our job or whatever.
(five one zero) 761-6559
We charge $20 for 15 minute for quick fixes.